Hi FreeSurfer specialists,

we have problems with a strong non-intensity in 3 Tesla data of GE (mainly temporal poles and occipital area).

We managed to rescue the occipital errors by a pre-Bias-field correction using SPM, but would of course try

to optimize this in recon-all itself.

When I open the recon-all scrip tin FS v7.1.1 I can find no difference in the parameters depending on if the

the flag "-3T" is set or not.

In both cases the parameters forwarded are:

--n 1 --proto-iters 1000 --distance 50

(in line 1536 and line 1540 of /bin/recon-all.)

 Could someone explain this?

What could be done (manual corrections etc. are obsolete due to the large sample size...) to improve the WM detection

in the temporolateral/polar area (subsequently cortex detection)? The brainmask looks okay; the ribbon.mgz shows the

cut off lateral parts of the cortex.

Thanks in advance for any hints,

Philipp